Lie detector tests and the CCMA
A polygraph test, also called a “lie detector test”, is used to determine whether a person is telling the truth. It is very important to note that polygraph tests must be conducted voluntarily and the consent to be examined must be in writing. Polygraph results are mostly used to assist investigators by pointing out the suspects. There is currently no legislation regulating the use of the polygraph, and for that reason, there is nothing preventing polygraph test results being presented as evidence in our courts of law.
Polygraph results have been submitted and accepted in a number of Commission for Conciliation, Mediation and Arbitration (CCMA) cases, and those results are submitted during internal investigations and disciplinary hearings to strengthen other evidence. Polygraph results can be used in labour matters and disciplinary hearings conducted in the work place.
With regards to disciplinary hearings in the work place, bear in mind that employees can’t be dismissed merely because they failed to pass the polygraph test. The commissioner noted, in the case of SACCAWU obo Khakhatiba v Country Meat Market (pty) ltd (2008) 17 CCMA, that the employee was dismissed mainly because he failed to pass the polygraph test. The commissioner reviewed case law on the admissibility of the polygraph test results, and held that labour tribunals attach little weight to such evidence because poly graph test results intrude in an area that the commission is itself enjoined to decide. More evidence than polygraph test results is needed to prove that an employee is guilty of misconduct. The dismissal in this case was ruled substantively and procedurally unfair, and the employee was reinstated.
This does not mean that employers cannot use polygraph testing. However, there are some strict rules that need to be complied with when conducting the polygraph test. Such rules are that the employer cannot force any employee to submit to the test, and the employer should agree with the polygraphers on the questions to be asked. In the case of Mncube & Cash Paymaster Services (Pty) Ltd KN1583 (1997), the commissioner accepted the polygrapher as an expert witness whose evidence needed to be tested for reliability.
In the case of Harmse & Rainbow Farms (Pty) Ltd, out of fifteen employees, Mr Harmse was the only one who failed the polygraph test. He declined the opportunity of another test. The employer dismissed Mr Harmse on the basis of breach of trust.
Proper polygraph procedures comply in respect with the South African Constitution and the Labour Relations Act, and promote fair labour practices and respect for the human rights of the examinee, because it gives the innocent person an opportunity to be heard and to prove their innocence.